1. Field of the Present Invention
The present invention relates to a thin film transistor-liquid crystal display (hereinafter "TFT-LCD") color television set, and more particularly, to a thin film matrix circuit for improving the picture quality and simplifying the structure of an image signal drive unit.
2. Description of the Prior Art
As shown in FIG. 1, a conventional thin film active matrix circuits utilized for an LCD drive unit are known in the prior art. For example, such thin film active matrix circuit includes gate bus lines 7 arranged in the transverse direction to supply scanning signals for actuating drains 3 connected to respective pixels 2 such as red R, green G, and blue B so as to perform the polarization; source bus lines 8 arranged below the gate bus lines 7; and a part of each pixel 2 cut out to accommodate a gate 4, a source 5 and a drain 3 of a thin film transistor 1 so that the pixels of two kinds of colors from red R, green G, and blue B can be controlled.
In such conventional thin film active matrix, when the transistor is turned on or off by scanning signals applied through the gate bus lines 7, the voltage is selectively applied to the pixels 2 through contacting portions 6 of the drain/pixel, and thus the LCDs are selectively polarized. At this time, the light on the rear side of an LCD panel passes through the pixels 2 in which the LCDs are polarized so that the image signals with respect to red R, green G and blue B corresponding to the respective pixels 2 are reproduced on the screen.
However, since one of the source bus lines 8 is connected to the sources 5 of the thin film transistors 1 which regulate the pixels of two kinds of colors and image signals of two kinds of colors are carried on one source bus line 8, the structure of the signal drive unit is complicating. Furthermore, in manufacturing of the thin film transistor 1 which is the LCD drive unit of each of the pixels 2, since the source bus lines 8 cross the gate bus lines 7, the area of the pixels 2 is decreased and therefore the effective region of the screen is decreased. Also, since each pixel 2 is of a step shape, the gaps between adjacent pixels 2 in the longitudinal direction are not uniform thereby the uniformity of the picture quality cannot be obtained.